The Carlton (go to 0:55 in the film clip, above) was the setting for the 1955 Alfred Hitchcock thriller To Catch A Thief, starring Cary Grant as a reformed diamond thief who is suspected of returning to his old ways. In the movie, the real thief is nabbed by Grant during a hot pursuit. In real life, the Carlton bijou bandit is still at large.

Here are five reasons why Lucky Pierre, the latest Cat Burglar of Cannes, has so far been successful in what may turn out to be the largest jewelry heist in history.

Location. Putting a bull's eye on the diamond stash was probably a mistake. Rich people with jewelry go to Cannes, which was the target of two major jewelry heists in May and numerous others over the years. The luxurious Carlton, the setting for To Catch A Thief, was the target of a $45 million jewel theft in 1994. Storing diamonds there, in that hotel, in that city, is like hiding a ten-pack of Jimmy Dean country sausages under your dog's sleeping pillow.

Communication. You can't make this up: Somebody forgot to tell the police about the jewelry exhibition. When the police ultimately were informed of the jewel theft, they said, "Jewels? What jewels?" When they were told, "You know, the jewels from the jewelry exhibition," they said, "Exhibition? What exhibition?" Zakaria Rami, a 16-year employee of the Carlton Hotel, told Associated Press, "If police knew there was $100 million in jewelry, I think they would have put a patrol car there."

Protection. Using the equivalent of mall cops as diamond guards is rarely a good idea, but that's about what happened. Just as the minimum-wage shopping-center rent-a-cop texting his girlfriend from the Desert Moon Cafè at the Food Court is not allowed to carry a weapon, so too are private security guards in France prevented from having guns. Apparently the agents protecting the jewelry exhibition were armed only with day-old baguettes and a very strong Camembert, which proved nearly useless when faced with the gun-wielding robber.

Precaution. Whenever I squire my wife anywhere--to the local diner, an Alice Cooper comeback concert, or a jewelry exhibition on the Riviera, the one thing she always says to me is, "Hey, did you lock up?" Too bad they didn't hire her to head up security over the sparklers at the Carlton. Turns out light-fingered Lucky Pierre, the thief, entered the hotel exhibition space by way of an open glass door that--oh dear, um, how to put this?--should have been locked! In the world of high-stakes security, folks, locking the door to a room full of jewels is not Rule #1. It's Rule #1, #2, #3, #4, and #5. Rule #6? Double-check that you locked the damn door.

Identification. There are certain tell-tale signs that someone is a suspicious character. If you've studied law-enforcement as I have (12 years of Law & Order reruns), you know the word I mean: hinky. Well, Lucky Pierre was hinky. Witnesses said that the baseball-cap wearing man who stole the jewels was wearing a scarf over his face when he entered the hotel. That should have been the tip-off right there, because no self-respecting Frenchman would be caught dead wearing a baseball cap. Très gauche.

Mark Orwoll is the International Editor of Travel + Leisure. You can follow him on Twitter @orwoll and "Like" him on Facebook.